The present invention relates generally to containers, and more particularly to glass containers having one or more frangible seals.
Sealed glass containers are used in a wide variety of applications. One such application involves the collection of discrete air samples. One common type of air sampling container is formed as a tube having sealed tapered ends. The tube is commonly packed with a sampling media to adsorb or react with one or more target airborne compounds. In practice, the tube remains sealed until just before use thereby ensuring the integrity of the sampling media and the interior space of the tube.
In operation, an air sampling technician, at the desired air sampling location, scores the tapered ends of the air sampling tube with a file and breaks off both of the tapered ends along the score thereby creating an open passage through the interior space of the tube. Next, a free end of polymeric tubing, which is attached to a pump at the other end, is slid over one end of the sampling tube thereby fluidly connecting the sampling tube with the pump. The pump is used to draw a predetermined volume of air to be sampled through the sampling tube. Once the desired volume of air is drawn, the sampling tube is removed from the polymeric tubing and both of its ends are sealed using plastic slide-on caps. The sampling tube is then transported to a laboratory for analysis.
Frequently, breaking off the ends of the sampling tube as described above results in the tube having jagged or uneven edges. These jagged edges pose a risk of injury to the sampling technician. Further, the polymeric tubing may not seal properly with the jagged edges, resulting in leakage between the pump and the tube and potentially compromising the integrity of the air sample. Moreover, the plastic caps used to seal the sampling tube after the air sample has been collected may be cut by the jagged edges thereby potentially resulting in the loss of collected sample or exposing the interior space of the tube to contamination. Accordingly, there is a need for an improved air sampling tube.
Another application for sealed glass containers is the preservation of fluids susceptible to volatilization or evaporation. The shelf-life of many of these fluids can be greatly increased by maintaining the compound in a sealed environment. One know approach is to package the fluid in a sealed glass vial or ampule. When the fluid is needed for use, a glass seal is broken and the fluid is poured from the ampule. Any unused fluid is either transferred to a sealable container for storage or discarded resulting in waste. Accordingly, there is a need for a sealed glass ampule having a cap.